Gravitational and Frictional Forces

What is gravitational force?

• Gravitational force is the force of attraction between two objects with different densities.

• Gravitational force is the force of attraction between two objects with mass.

• Gravitational force is the force of attraction between two objects with electric charge.

• Gravitational force is the force of repulsion between two objects with mass.

What are the two types of frictional force?

• Dynamic friction and potential friction

• Frictional force and gravitational force

• Sliding friction and rolling friction

• Static friction and kinetic friction

How does static friction differ from kinetic friction?

• Static friction increases with speed, while kinetic friction decreases with speed.

• Static friction is stronger than kinetic friction, while kinetic friction is weaker than static friction.

• Static friction prevents an object from moving, while kinetic friction opposes the motion of an object that is already moving.

• Static friction occurs between two stationary objects, while kinetic friction occurs between two moving objects.

Give an example of rolling friction in everyday life.

• A bicycle smoothly gliding on a flat road

• An example of rolling friction in everyday life is when a car's tires roll on the road, creating resistance that slows down the car.

• A skateboard rolling on a well-oiled surface

• A ball rolling on a smooth surface with no resistance

Explain the concept of gravitational force in simple terms.

• Gravitational force is the force of repulsion between two objects with mass.

• Gravitational force is the force of attraction between an object and the Earth's magnetic field.

• Gravitational force is the force of attraction between two objects with mass.

• Gravitational force only affects objects on Earth, not in space.

What are the factors that affect the force of friction?

• Material of the object, distance traveled, air pressure

• Nature of the surfaces, normal force, presence of lubricants or contaminants

• Humidity, weight of the object, time of day

• Temperature, velocity, color of the surfaces

How can lubricants help in reducing friction?

• Lubricants evaporate quickly and make surfaces more rough

• Lubricants reduce friction by creating a barrier between moving surfaces.

• Lubricants have no effect on reducing friction

• Lubricants increase friction by attracting more dirt and debris

Describe the role of air resistance in friction.

• Air resistance has no effect on the friction experienced by an object moving through the air.

• Air resistance decreases the friction experienced by an object moving through the air.

• Air resistance only affects the speed of an object, not the friction.

• Air resistance increases the friction experienced by an object moving through the air.

What is the formula to calculate gravitational force?

• F = G * (m1 + m2) / r^2

• F = G * (m1 - m2) / r^2

• F = G * (m1 * m2) / r^2

• F = G * (m1 * m2) * r^2

How does the mass of an object affect the gravitational force?

• The gravitational force increases with the mass of an object.

• Gravitational force is inversely proportional to the mass of an object.

• The mass of an object has no effect on gravitational force.

• The gravitational force decreases with the mass of an object.